Haven't seen your design, but my .02 anyway-if you are switching the
primary with a SS relay, be careful of letting it cook as you described.
The first indication the relay is overloading is when it pukes. How
about posting some pics and a schematic in the dropbox?
Mine:
http://www.metalworking.com/dropbox/...retired_files/
See welder00.txt and the associated jpgs
JR
Dweller in the cellar

Bob Engelhardt wrote:
After trying a couple of piece=of-cake welds, I thought I'd push the
envelope and tried it on 2 pieces of 1/8" mild steel. It had to let it
cook a while, but it was a perfect weld, as far as I can tell (peel
test). I don't think that I need to try for anything thicker 8-)

http://home.comcast.net/~bobengelhardt/weld.jpg

Bob


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Home Page: http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
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No skeletons in the closet; just decomposing corpses
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Dependence is Vulnerability:
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